diff options
Diffstat (limited to 'usr/src')
| -rw-r--r-- | usr/src/uts/common/os/ddi_timer.c | 33 |
1 files changed, 29 insertions, 4 deletions
diff --git a/usr/src/uts/common/os/ddi_timer.c b/usr/src/uts/common/os/ddi_timer.c index b52cd339a8..623492f77c 100644 --- a/usr/src/uts/common/os/ddi_timer.c +++ b/usr/src/uts/common/os/ddi_timer.c @@ -48,11 +48,36 @@ static kmem_cache_t *req_cache; /* kmem cache for timeout request */ /* - * taskq for timer + * taskq parameters for cyclic_timer + * + * timer_taskq_num: + * timer_taskq_num represents the number of taskq threads. + * Currently 4 threads are pooled to handle periodic timeout requests. + * This number is chosen based on the fact that the callout (one-time + * timeout framework) uses 8 threads with TQ_NOSLEEP; the periodic timeout + * calls taskq_dispatch() with TQ_SLEEP instead, and in this case, 4 threads + * should be sufficient to handle periodic timeout requests. (see also + * timer_taskq_max_num below) + * + * timer_taskq_min_num: + * timer_taskq_min_num represents the number of pre-populated taskq_ent + * structures, and this variable holds the same value as timer_taskq_num does. + * + * timer_taskq_max_num: + * Since TQ_SLEEP is set when taskq_dispatch() is called, the framework waits + * for one second if more taskq_ent structures than timer_taskq_max_num are + * required. However, from the timeout point of view, one second is much longer + * than expected, and to prevent this occurrence, timer_taskq_max_num should + * hold a sufficiently-large value, which is 128 here. Note that since the size + * of taskq_ent_t is relatively small, this doesn't use up the resource so much. + * (Currently the size is less than 8k at most) + * + * About the detailed explanation of the taskq function arguments, please see + * usr/src/uts/common/os/taskq.c. */ -int timer_taskq_num = 1; /* initial thread number */ -int timer_taskq_min_num = 4; /* minimum taskq thread pool */ -int timer_taskq_max_num = 16; /* maximum taskq thread pool */ +int timer_taskq_num = 4; /* taskq thread number */ +int timer_taskq_min_num = 4; /* min. number of taskq_ent structs */ +int timer_taskq_max_num = 128; /* max. number of taskq_ent structs */ static taskq_t *tm_taskq; /* taskq thread pool */ static kthread_t *tm_work_thread; /* work thread invoking taskq */ |